This application claims priority of European Patent Application No.98460040.3, which was filed on Sep. 25, 1998.
The field of the invention is that of telephone systems. The invention can be applied especially to the management of private and/or public telephone automatic branch exchanges. More specifically, the invention relates to a method for the management of a telephone automatic branch exchange, an external management device as well as a corresponding branch exchange.
In general, a private automatic branch exchange manages a plurality of objects, geographically distributed within the premises of a firm. Examples of such objects are, for example, voice message mailboxes, telephone sets and answering machines. Each object is characterized by at last one parameter. The manager defines the parameter or parameters of at least certain of the objects and/or he loads and/or saves and/or modifies these parameters. The modification may be used to update the configuration or eradicate the bugs from the configuration of an automatic branch exchange. Configuration bugs of this kind may be the cause of relatively serious malfunctioning that could lead to a dysfunctioning or even the blocking of the automatic branch exchange.
Hereinafter in the present patent document, the term xe2x80x9cmanagementxe2x80x9d of a telephone branch exchange refers in particular to the following four series of functions:
the functions of loading the configuration in an automatic branch exchange;
the functions of saving the configuration of an automatic branch exchange;
the functions of updating the configuration of an automatic branch exchange;
the functions of remote maintenance of the configuration of an automatic branch exchange.
Hereinafter in the description, the term xe2x80x9cmanagerxe2x80x9d will designate a human operator performing at least certain of the above-mentioned functions of management.
There are several distinct known ways of managing an automatic branch exchange. Thus, a first known solution for loading the configuration into an automatic branch exchange, known as the xe2x80x9cvideotexxe2x80x9d (registered mark) system, enables the connection of a Minitel (registered mark) terminal to an automatic branch exchange through a serial link by means of a modem,
According to this first approach, a manager types out a textual configuration command on a keyboard of the Minitel (registered mark) and sends this command to the automatic branch exchange to be configured. The textual message is received and then interpreted by the automatic branch exchange to define or modify at least one parameter of an object managed by the automatic branch exchange.
However this first solution is not advantageous.
First of all, it makes it necessary to type the textual commands one by one. Thus, if the manager has to define a large number of parameters, this means that he has to type a corresponding number of commands. The first solution therefore is very cumbersome to implement.
Then, the first solution does not enable the transmission of commands except in one direction, namely from the Minitel to the configuration server of the automatic branch exchange. In other words, it is not possible to retrieve the configuration commands sent to the automatic branch exchange.
Furthermore, since it is not possible to retrieve the transmitted configuration commands, the first solution prevents the remote maintenance of the configuration of an automatic branch exchange, or makes it difficult to carry out this remote maintenance,
Finally, the first approach dictates a permanent connection with the concerned telephone automatic branch exchange.
A second known method of loading a configuration into an automatic branch exchange implements a protocol called a xe2x80x9csimple network management protocolxe2x80x9d on a computer that is connected to an automatic branch exchange to a series link by means of a modem. This protocol is presented for example in the published document RFC 1157 by J. Case, M. Fedor, M, Schoffstall and J. Davin, May 1990.
According to this second approach, a manager has two commands for the remote management of an automatic branch exchange by means of a computer. A first command enables the retrieval of a parameter of an, object and a second command enables this parameter to be modified.
This second approach has several drawbacks.
Indeed, if the manager wishes to modify a large number of parameters, the second approach makes it necessary to perform a large number of processing operations since two operations have to be performed to modify only one parameter. The second approach is therefore cumbersome.
Furthermore, it is impossible for the manager to retrieve all the configuration commands of the automatic branch exchange.
Finally, the second approach requires a permanent connection between the computer and the automatic branch exchange, and this involves major connection costs.
There is also a third known approach providing means for the consultation of the data elements pertaining to the configuration of an automatic branch exchange connected to an automatic branch exchange (locally or at a distance) through a series link by means of a modem.
According to this third approach, a manager may consult raw configuration data of the automatic branch exchange in blocks and therefore memorize raw data of this kind in the form of blocks. The manager can then modify the raw data after having carried out an interpretation of said data.
This third approach also has many drawbacks.
First of all, the manager is obliged to know the memory organization of the data elements in order to access the different parameters before modifying them as the case may be. Such an obligation to know requires the manager to perform a not negligible and even substantial job of analysis and interpretation on the recovered raw data Errors may be inserted following a wrong interpretation and/or modification by the manager. Now, the impact of such errors may give rise to major or even catastrophic malfunctioning for the users of the automatic branch exchange. In certain extreme cases, these errors may lead to a paralysis of the entire system.
Furthermore, it may happen that the manager can modify retrieved raw data only in data blocks. Consequently, the manager can work only on data blocks. This increases his workload since he must interpret an entire block of raw data before being able, if necessary, to modify some of it. Any modification therefore represents an operation that is cumbersome and difficult to implement.
Finally, he must know the exact memory location since the organization of the data blocks must be followed precisely. Indeed, the organization of the raw data, as regards their memory addresses, should not vary in order to avoid any configuration bug.
The three current approaches require substantial time of connection with the automatic branch exchange in order to transfer commands and/or data from or to the automatic branch exchange.
It is impossible to configure an automatic branch exchange off-line,
Furthermore, these approaches do not enable a simple, low-cost implementation of the configuration of an automatic branch exchange without the interpretation of the operation of the automatic branch exchange. Again, it is not possible to preserve the parameters of the current configuration of an automatic branch exchange before updating it, for example in order to install a new version of a configuration program on the automatic branch exchange.
The present invention is designed especially to overcome these different drawbacks of the prior art. More specifically, one of the goals of the present invention is to provide a method for the management of a telephone automatic branch exchange and a corresponding external management device used to assemble and simplify all the management functions of an automatic branch exchange and to make their uses faster and more flexible.
Another goal of the invention is to provide a method of this kind and a device of this kind used to display at least one portion of the configuration of an automatic branch exchange.
Another goal of the invention is to provide a method of this kind and a device of this kind used to rapatriate or upload at least a part of the current configuration from an automatic branch exchange to said external device.
Another goal of the invention is to provide a method of this kind and a device of his kind to diminish the time of analysis and interpretation of the configuration instructions in order to modify at least certain of the object parameters.
An additional goal of the invention is to provide a method of this kind and a device of this kind to diminish the risk of errors within the configuration commands.
Another goal of the invention is to enable the manager to exercise at least certain of the management functions on an emulated version of the configuration of an automatic branch exchange so as to locally prepare a new configuration which could subsequently be remote loaded into an automatic branch exchange.
Another goal of the invention is to enable the optimizing of the connection time needed to transfer a part or all the configuration commands from or to an automatic branch exchange and therefore to optimize the cost of operation of the link with this automatic branch exchange.
These various goals as well as others which shall appear hereinafter are achieved according to the invention by means of a method for the management of a telephone automatic branch exchange in which the telephone automatic branch exchange is provided with a management program that makes use of the raw configuration data to ensure the operation of said telephone automatic branch exchange, characterized in that the method comprises three main distinct phases of management:
a phase of the initialization of a basic configuration for said telephone automatic exchange;
a phase of the extraction of a configuration diagram representing said basic configuration;
an optional phase for the transfer of said configuration diagram from an external management device to said telephone automatic branch exchange or vice versa; these being phases in which:
said initialization phase of a basic configuration essentially consists in:
structuring the configuration of said telephone automatic branch exchange in the form of a plurality of distinct objects and/or sub-objects each characterized by at least one parameter;
describing in detail said basic configuration in the form of a raw data base that can be exploited by said program for the management of said telephone automatic branch exchange;
said phase for the extraction of a configuration diagram that represents said basic configuration essentially consists in:
exploring said basic configuration on all or part of said raw data base so as descriptive condensed image of said basic configuration in the form of a configuration instructions constituted by a list of configuration instructions;
xe2x80x83said optional transfer phase essentially consists in:
xe2x80x83exporting or downloading all or part of said diagram of configuration instructions from said external management device to said telephone automatic branch exchange in order to configure said telephone automatic branch exchange; and/or
xe2x80x83preparing and uploading all or a part of said diagram of configuration instructions from said telephone automatic branch exchange to said external management device so as to store a partial or full image of said current basic configuration of said telephone automatic branch exchange in storage means accessible from said external management device.
Thus, the invention relies on a novel approach to the management of a telephone automatic branch exchange. Indeed, instead of creating means to manage an automatic branch exchange by offering direct access to the configuration parameters, it is planned to transfer a partial or total reconstituted image of the basic configuration of the automatic branch exchange in the form of a diagram of configuration instructions. This configuration image is reconstituted from a consultation of the raw data of configuration of the automatic branch exchange. This configuration image is prepared during the phase to extraction of a configuration diagram representing the basic configuration. It is this configuration image that will be loaded, saved, modified, and/or updated by the manager. The automatic branch exchange and the external device, for their part, interpret the configuration image, enabling the reconversion of the configuration instructions into raw configuration data that can be exploited by an appropriate management program.
In other words, the main principle of the invention is based on the creation of at least three hierarchical levels of commands, namely a first layer called the upper layer, a second layer of textual configuration commands constituted by configuration instructions and a third layer of commands for the interpretation of these textual commands.
The first layer comprises a macrocommand used during an optional phase of transfer of the configuration instructions diagram. The macrocommand enables a manager to activate a downloading of all or a part of the diagram of instructions of a configuration, from a device, called an external device, which is at a distance from the automatic branch exchange to an automatic branch exchange. The diagram is prepared beforehand by the manager within the to prepare a diagram of external management device or it is retrieved from another automatic branch exchange following an uploading of a part or all of the diagram of instructions of the current configuration as described here below. In reverse, and again by means of the macrocommand, the manager may reconstitute all or a part of the diagram of instructions of the current configuration of an automatic branch exchange and activate an uploading of this totality or part of the reconstructed configuration diagram to an external management device.
The second layer comprises configuration instructions obtained during the phase of extraction of the configuration diagram, the number of which is optimal because these instructions are created from a set of configuration commands that are explicit and appropriate to the operations to be performed on the parameter(s) of the different objects and/or sub-objects. The configuration instructions are furthermore organized according to a defined architecture called a diagram of configuration instructions in keeping with a unique formalism.
The third layer comprises commands enabling the performance, possibly through a lower additional layer, of the textual configuration commands. It is precisely the third layer that is characterizes the parameter or parameters of these different object(s) and/or sub-object(s) of the structure of the configuration. This third layer is used during the phase of initialization of a basic configuration enabling the setting up of a raw data base that can be exploited by the management program of the automatic branch exchange.
It will be noted that the number of objects and/or sub-objects as well as the number of parameters characterizing each object or sub-object in the configuration structure may be any number.
It must also be noted that a simple launching of a macrocommand activates the transfer of a part or the totality of the desired configuration instructions, in the form of a configuration diagram, from an external device to an automatic branch exchange without interrupting its operation. Conversely, i.e. to carry out an uploading of all or a part of the configuration diagram from an automatic branch exchange to an external device, again however with a simple launching of the macrocommand, the activator activates initially the preparation of the desired configuration diagram and, secondly, the transfer of this diagram into storage means enabling the saving of a partial or complete descriptive image of the raw data base.
The connection time pertaining to the uploading of the configuration diagram therefore corresponds to the transfer time of the configuration instructions. It may be recalled, that in the approaches known prior to the invention, this connection time is considerable since the manager must mobilize the connection by issuing a precise question per parameter of object and/or sub-object that it needs to retrieve.
Following the partial or full uploading of the configuration instructions, the manager may reconstitute, especially within the external device, a faithful image of the configuration instructions of the automatic branch exchange since the image has an identical structure and identical values of objects and/or sub-objects and/or parameters. Since the configuration instructions are explicit, the lime of analysis and interpretation of the configuration instructions is reduced. The image of the configuration instructions in particular enables the manager to locally (within the external device) emulate the configuration of the remote automatic branch exchange in order to obtain an image of the configuration of the automatic branch exchange. This image of the operation of the automatic branch exchange, especially through a set of explicit commands, facilitates the analysis of the configuration and therefore any processing to be made on the current configuration of the uploaded automatic branch exchange. It makes it possible especially to detect functional errors in the configuration instructions. The detected functional errors enable the deduction therefrom of the errors committed within the configuration instructions, thus making it easier to detect the required modifications.
Furthermore, the image of the configuration has a simple structure for the presentation of information in such a way that it simplifies the consultation of desired information elements.
Advantageously; at least certain of said objects and/or sub-objects are linked to other said objects and/or sub-objects in a tree structure.
In this way, the tree structure may enable the breakdown, entirely or partially, of the configuration of the automatic branch exchange into sub-divisions which may possibly be hierarchically organized. To do this, the root of the tree structure represents a main object, a ramification represents a sub-object, and sub-ramifications, if any, represent other sub-objects and, finally, one or more terminal branches represent one or more parameters associated with the characterizing of the object.
It will be noted that the invention imposes no constraint on the number of possible levels of possible sub-objects between each object and the parameters characterizing this sub-object.
Advantageously, said raw data base, for each object and/or sub-object, comprises values of said parameters and/or addresses of the objects and/or sub-objects with which said object and/or said sub-object is linked within said tree structure.
In this way, an organization of this kind of the tree structure of the raw data base enables a meshing of the data elements. Consequently, the selection of only one link data element of the tree structure makes it possible, through the simple, successive and recursive inspection of the data of the links adjoining the selected link data, to consult a part or the totality of the basic configuration of the desired automatic branch exchange.
Preferably, said phase for the extraction of a configuration diagram representing said basic configuration essentially consists in:
exploring said basic configuration on all or part of said tree structure so as to prepare a descriptive condensed image of said basic configuration in the form of a diagram of configuration instructions constituted by a list of configuration instructions.
In this way, the descriptive condensed image of the basic configuration provides a structure for the presentation of the information that is modelled on the tree structure of the raw data base enabling the fast reading of this tree structure, A fast reading operation of this kind is possible because the resulting construction of the image bears a strong correlation with the tree structure of the configuration.
Preferably, there is at least one configuration and transfer macrocommand enabling the activation of the partial or complete transfer of said diagram of said configuration instructions of said telephone automatic branch exchange, from said telephone automatic branch exchange to a device external to said telephone automatic branch exchange or vice versa, in the framework of management functions of said telephone automatic branch exchange, belonging to the group comprising:
the functions of loading a configuration into a telephone automatic branch exchange;
the functions of saving the current configuration of said telephone automatic branch exchange;
the functions of updating the current configuration of said telephone automatic branch exchange;
the functions of the remote maintenance of the current configuration of said telephone automatic branch exchange.
Thus, a single configuration and transfer macrocommand enables the simplified activation of all the management functions of an automatic branch exchange depending on the context in which it is used.
Furthermore, the performance of these various functions is made faster since the connection times are reduced to the transfer time of the configuration instructions. The costs of running the line between the external device and the automatic branch exchange concerned are therefore reduced.
Furthermore, the performance of all these functions is more flexible for only the use of the configuration and transfer macrocommand is necessary.
Advantageously, for said functions of the loading of a configuration in a telephone automatic branch exchange, said configuration and transfer macrocommand is used in order to:
at least partially prepare and download said diagram of configuration instructions from said external management device to said telephone automatic branch exchange;
reconstitute the basic configuration from said downloaded diagram of configuration instructions so as to ensure the configuration of said automatic branch exchange.
It will be understood thus that a manager may prepare a configuration within the external device off-line or locally. Then, once the configuration is ready, depending on possible emulations of different versions of the prepared configuration, a loading of the configuration desired may be made by means of a single activation of the configuration and transfer macrocommand.
It must be noted that a loading of a configuration that a manager is preparing within the external device may also be done simultaneously, on-line (namely during a connection with the automatic branch exchange to be managed), if necessary by means of a macrocommand.
Preferably, for said functions of saving the current configuration of said telephone automatic branch exchange, said configuration and transfer macrocommand is used to:
at least partially prepare and upload said diagram of configuration instructions from said telephone automatic branch exchange to said external management device;
reconstitute the basic configuration from said uploaded diagram of configuration instructions and store said reconstituted basic configuration in storage means accessible from said external management device.
Thus, following an uploading of the configuration instructions, the manager may consult the instructions of the current configuration in good rime without having to make a new connection. The manager may furthermore locally recreate an image of the current configuration of the automatic branch exchange.
It must be noted that the storage means may be internal to the external device or else away from the device, for example in a storage zone proper to the means of interpretation of the configuration instructions of the automatic branch exchange without requiring a new connection with the external device.
Following the activation of this macrocommand to upload the configuration instructions, the manager may store them in the memory of the external device, in particular to modify them within the external device. The modification is done on at least certain of the parameters of objects and/or sub-objects characterizing the configuration. This modification may be used especially in order to reinject the modified configuration instructions during a loading of the modified configuration into the same automatic branch exchange. The modification performed makes it possible especially to carry out an updating of the configuration of the automatic branch exchange in question. The modification made may again be used especially to eradicate the detected errors in order to perform the remote maintenance of the configuration of the automatic branch exchange concerned.
Advantageously, for said updating functions of the current configuration of said telephone automatic branch exchange, said configuration and transfer macrocommand is used to:
at least partially prepare and upload said diagram of configuration instructions, from said telephone automatic branch exchange to said external management device;
update said diagram of instructions of the current configuration;
at least partially download said updated diagram of configuration instructions from said external management device to said telephone automatic branch exchange;
reconstitute the basic configuration downloaded from said diagram of configuration instructions so as to load an updated configuration into said telephone automatic branch exchange.
It will be noted that the updating of the instructions diagram of the current configuration of an automatic branch exchange may result from a reconstitution of the basic configuration followed by an updating of the reconstituted basic configuration and then a preparation of the configuration diagram from the updated basic configuration within the external device. Consequently, the updating may be done in a simple way on a remote site of the automatic branch exchange on which it is planned to update its configuration without being connected with this automatic branch exchange (i.e. in being off-line).
The connection time is therefore reduced to the time needed to download the updated configuration instructions to the concerned automatic branch exchange. By contrast, in the prior art, a simple updating of the configuration is difficult since an updating operation of this kind requires a substantial amount of time to analyze and interpret the data retrieved while at the same time remaining connected with the automatic branch exchange.
Preferably, for said functions of remote maintenance of the current configuration of said telephone automatic branch exchange, said configuration and transfer macrocommand is used to:
at least partially prepare and upload said diagram of configuration instructions from said telephone automatic branch exchange to said external management device;
modify said diagram of instructions of the current configuration as a function of remote maintenance imperatives;
at least partially download said modified diagram of configuration instructions from said external management device to said telephone automatic branch exchange;
reconstitute the basic configuration downloaded from said downloaded diagram of configuration instructions so as to load a modified configuration into said telephone automatic branch exchange.
It is clear that a configuration may result from additions and/or eliminations of configuration instructions relating to at least one configuration parameter. This modification makes it possible for example, at one and the same local site, to replace an automatic branch exchange by a new automatic branch exchange or again replace the current version of the management program by a new version attached to one and the same automatic branch exchange.
Just as in the case of the updating functions, it is possible for a manager to analyze the configuration instructions of a xe2x80x9cmalfunctioningxe2x80x9d automatic branch exchange within the external device. In other words, the maintenance may be performed on a remote site of the xe2x80x9cmalfunctioningxe2x80x9d automatic branch exchange in order to eradicate its bug or bugs without being connected to the concerned automatic branch exchange. The connection time is therefore also reduced to the time needed to download the modified configuration instructions to the automatic branch exchange concerned.
It will be understood that the modification made on the diagram of configuration instructions may result from a reconstitution of the basic configuration that reveals the errors, a modification of the reconstituted basic configuration enabling the elimination of errors and then a preparation of the configuration diagram modified from the modified basic configuration.
It is clear however that a detection of errors may result especially from a simple observation of bugs appearing on the image of the uploaded current configuration and that a consecutive loading of the configuration instructions, for example in the course of a connection with the automatic branch exchange in question, enables the elimination of the detected errors.
Advantageously, said configuration instructions constituting said diagram of configuration instructions are composed by using a set of available configuration commands, said instructions enabling the association, with each of said objects and/or sub-objects, of said at least one parameter characterizing it.
Preferably, said configuration commands of said set of configuration commands belong to the group comprising:
a command xe2x80x9cSELECTxe2x80x9d providing for the selection of the object and/or sub-object associated with said command xe2x80x9cSELECTxe2x80x9d:
a command xe2x80x9cCHANGExe2x80x9d modifying the value of the parameter of the current object and/or sub-object associated with said command xe2x80x9cCHANGExe2x80x9d;
a command xe2x80x9cVALIDxe2x80x9d validating the value or values of the defined parameter or parameters associated with the currently selected object and/or sub-object;
a command xe2x80x9cUPxe2x80x9d providing for the deselection in said structure of the configuration of the currently selected object and/or sub-object.
This list is not restrictive.
Advantageously, said configuration and transfer macrocommand fulfils at least one of the following two functions:
the preparation of said diagram of configuration instructions from an exploration of the basic configuration of said telephone automatic branch exchange;
the downloading or the partial or full uploading of said diagram of configuration instructions from said external management device to said telephone automatic branch exchange or vice versa
It must be noted that the manager, from the external device, activates the configuration and transfer macrocommand to perform either:
a downloading of a part or the totality of the diagram of configuration instructions, that had been previously prepared (off-line with respect to the automatic branch exchange to be managed) within the external device by a manager (xe2x80x9cTRANSFERxe2x80x9d function); and/or
a preparing and a simultaneous downloading of a part or the totality of the instructions diagram of the current configuration of an automatic branch exchange during connection with the automatic branch exchange to transmit new configuration instructions to an automatic branch exchange (xe2x80x9cTRANSFERxe2x80x9d function); and/or
a preparing of a part or the totality of the diagram of instructions of the current configuration of an automatic branch exchange followed by its uploading to retrieve the instructions of the current configuration within the external device (xe2x80x9cSAVExe2x80x9d function).
The invention also relates to an external device for the management of a telephone automatic branch exchange. An external device of this kind comprises means to implement at least certain of said management functions of an automatic branch exchange described here above.
The term xe2x80x9cexternal management devicexe2x80x9d designates a device external to the automatic branch exchange enabling the management of this automatic branch exchange.
Advantageously, said external management device furthermore comprises:
means for the interpretation, updating and/or modification of a diagram of current configuration instructions of a telephone automatic branch exchange transferred into said external management device by means of said configuration and transfer macrocommand; and/or
means for the reconstitution of a part or all of the basic configuration of said telephone automatic branch exchange from said diagram of configuration instructions, and for the updating and/or modification of said reconstituted basic configuration;
means to prepare said diagram of configuration instructions from an exploration of the saved and/or updated and/or modified basic configuration (60) of said telephone automatic branch exchange.
Since the, external device comprises means for the interpretation of a diagram of configuration instructions, a manager may locally recreate an exact image of the configuration of the remote automatic branch exchange. Such a characteristic also makes it possible to prepare and define a diagram of configuration instructions off-line. This diagram of configuration instructions can then be remote-loaded at a later date into an automatic branch exchange.
Indeed, the manager can implement the means of interpretation to obtain an emulation of the prepared or uploaded configuration in order to diagnose malfunctions, if any, in order to eradicate then?. The time needed for troubleshooting is considerably smaller than in the prior art, for no prior art solution emulates all or part of the current configuration of an automatic branch exchange  less than  less than locally  greater than  greater than namely within an external management device.
Thus it is possible, within the external device, to have an architecture identical to chat of an automatic branch exchange so that this external device can carry out a part or the totality of the instructions of its current configuration in a manner similar to this automatic branch exchange.
Preferably, said external management device furthermore comprises means for the storage of the partial or complete basic configuration of said telephone automatic branch exchange designed to be loaded and/or saved and/or updated and/or modified.
A characteristic of this kind enables the saving xe2x80x9cin memoryxe2x80x9d within the external management device of a faithful image of at least a part or the totality of the current configuration of an automatic branch exchange.
Advantageously, said external management device is connected to a telephone automatic branch exchange through a serial link and/or telephone link and/or Ethernet link.
In a preferred embodiment of the invention, said external management device is integrated into a dedicated configuration computer or into another telephone automatic branch exchange.
It will be understood that it may also be of utility to connect this external device to two automatic branch exchange devices, namely:
a first automatic branch exchange whose configuration has no bug, in order to recover the diagram of instructions of the current configuration of this first automatic branch exchange;
a second automatic branch exchange, distinct from the first automatic branch exchange, whose configuration has at least one bug and/or one imperfection.
Indeed, a manager using the external device can activate the configuration and transfer macrocommand in order to retrieve at least one part of the diagram of configuration instructions of the first automatic branch exchange (in the case of uploading). Then, the manager, as the case may be, depending on the operating requirements of the second automatic branch exchange, may adapt at least certain of the configuration instructions uploaded from the first automatic branch exchange and reinject these instructions, at least partly, into the second automatic branch exchange. To do so, the manager activates (this is the case of downloading) the transfer and configuration macrocommand for a second time in order to eradicate the bugs and/or perfect the configuration of the second automatic branch exchange.
The invention also relates to an automatic branch exchange of the type designed to implement the method described here above.